These Arizona Rangers were gathered together in 1903. The rifles that I can identify are all 1895 Winchesters. In 1903 the total Ranger force consisted of 26 men. I count 25 assembled for this picture. The Ranger Act of 1901 required that every ranger carry an 1895 Winchester and a Colt Single Action Army chambered in .45 Colt. One Ranger, private Lonnie McDonald, had been wounded in February of 1903, and he may not have yet recovered in time to be included in this photo. I see a few possible gunbelts, but the angle is precisely wrong to see any holstered Colts. Picture from historynet.com.
http://www.thetruthaboutguns.com/2014/11/dean-weingarten/arizona-rangers-group-photo-1903/